The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Present day servers (e.g., storage and blade servers) almost always incorporate a “service processor”. A service processor typically is a microcontroller embedded in the server or a server blade chassis, and used for remote management purposes. Frequently the service processor is located on a motherboard of a server or on a PCI card. The service processor is completely independent from the main CPU and the system operating system of the server. Thus, it is able to operate fully independently of the server's CPU and operating system, even if the server's CPU or operating system is locked up or otherwise inaccessible. Service processors are often used to perform one or more of following valuable functions/operations:                Power Management        Report Status (On/Off)        Report Consumption (Volts & Amps)        Control (On, Off, Reboot)        Thermal Management        Read Temperatures        Control Fan Speeds based on temperatures        Report fan failures (fan(s) not running at the correct speed)        Sensor Monitoring—Intrusion Alarm, etc.        Remote Console        Serial Port redirection via telnet/SSH        Remote Keyboard/Video/Mouse over IP        Remote Media—Ability to attach remote storage devices as emulated        USB devices        Log system events such as operating system (OS) crash, system boot        Configurable behaviors for system events such as alert generation and system shutdown        System Inventory—read Field Replaceable Unit (FRU) EEPROMs, PCI devicesMore specifically, one or more of the following functionalities may be provided using a service processor:        Remote power control—Servers can be remotely powered off, on, or cycled through service processors. This is one of the most useful features of service processors. Remote power control is used to restore servers that are locked up, to power down overheated servers, or to perform any other function that requires low-level interaction with the server.        Graceful shutdown support—Certain service processors support a remote power control command that actually sends a signal to the server operating system to shut down gracefully before actually power cycling or turning off the server. This prevents the possible effects of a “brute force” power cycle or shutdown, such as data corruption in the server hard drives and other undesirable outcomes.        Remote SoL console access—The server console can be accessed through the Ethernet interface of its service processor by using a standard telnet or Secure Shell (SSH) client in the same way it would be available through a regular serial port. If the server supports BIOS redirection to the serial port (which is usually the case with servers equipped with service processors), a user can have full access to the server console from the time it is booted up, through the BIOS and all the way up to the OS login prompt. This is very useful for remote troubleshooting.        Health monitoring—Service processors communicate with the appropriate sensor hardware in the server (e.g., fan speed monitors, voltage meters and temperature readers) to access and monitor vital server statistics so that server problems can be detected quickly. The health information can be stored on the server, sent to a remote storage device or communicated directly to the user workstation.        Remote ID LED control—Service processors allow the administrator to turn on or off the server's identification (ID) LED, which can be used to identify a specific server in a rack of multiple similar servers. This is especially useful when maintenance is needed on a server and the local technician who has physical access to the server does not have access to server information. In that case, the administrator can turn on the ID LED to visually designate for the local technician which server needs maintenance.        Local and server-based authentication—In order to access the service processor features, a user needs to log in to it first. The user database is usually stored locally in the service processor. Some service processors can also communicate with central authentication server mechanisms, such as LDAP and Active Directory.        Data encryption—The communication between the service processor and the user may be encrypted if the service processor supports communication protocols that allow for encryption, such as Secure Shell (SSH) or Secure Socket Layer (SSL). Most recent service processors support some level of data encryption.        System event log (SEL)—Service processors can store information about events related to the server hardware, such as chassis opening and closing, hard drive functional alarms, RAM test errors and so on. Those event logs can then be verified by the server administrators directly, or be used as the source for automated alerts.        Platform Event Traps (PET)—Service processors can be programmed with information about critical thresholds for server environmental variables, such as the maximum operating temperature, minimum CPU fan speed, etc. Based on those thresholds, it can then send out alerts (traps) to a management system, usually in SNMP format, so that the server administrator can take immediate action to remediate the issue at hand.        Data logging—Some service processors provide the ability to log the data flowing through the server's serial console, regardless of whether there is a user directly connected to that session at that time. This enables administrators to review the history of events that happened to the server before a certain issue occurred, providing a useful audit trail for change tracking and troubleshooting. Virtual keyboard/video/mouse (KVM) is similar to the Serial over Lan (SoL) feature but instead of exposing the server's text-based serial console to the user, Virtual KVM provides access to the server's graphical user interface (GUI). This is especially important for operating systems that rely heavily on their GUIs, such as Microsoft's WINDOWS® operating system.        Virtual Media—Certain service processors allow the server to access storage media such as CD-ROMs, floppy disks and even DVD-ROMs anywhere on the network—just as if they were directly attached to that server. This allows users to quickly move and copy data between their user workstations to the server (and vice versa), which is useful for emergency OS and application patch installations, as well as diagnostic testing and BIOS upgrades. Virtual Media, along with Virtual KVM, enables a true lights-out management experience using the interfaces and tools that users are already accustomed to in their daily routine.        
The service processor may include a component that is often referred to as a “BMC” (Baseband Management Controller). The Avocent Corporation provides the firmware for BMCs to various major server manufacturers. Some major service processor technologies include:                HP Integrated Lights Out (iLO)        IBM® Remote Supervisor Adapter (RSA)        Dell Remote Assistant Card (DRAC)        Sun Advanced Lights Out Management (ALOM)        Sun Integrated Lights Out Management (ILOM)        
Service processors are typically accessible through either a dedicated Ethernet interface (i.e., out-of-band) or a shared data Ethernet interface (i.e., sideband). Most of the features provided by service processors, as outlined above, are not new, and many of these features are available in some shape or form through other remote management solutions, such as console servers, KVM switches, IPDUs, etc. In fact, virtually all of the benefits provided by remote out-of-band management tools are available through service processors—lower Mean-Time-To-Repair (MTTR), operating cost savings and improved asset productivity. However, one key difference is that in the case of service processors, the complete feature set needed to reap those benefits is already included in the server, and furthermore is accessible through a single interface. Moreover, the single interface is Ethernet, the most ubiquitous network interface in the IT marketplace. This greatly simplifies the deployment of the remote server management infrastructure, making it easier for information technology managers to take advantage of these technologies. Additionally, the fact that service processors are embedded inside the server provides more granular and thorough visibility of the server's status, which allows for proactive and preventive management, as well as greater control of the overall server infrastructure. Features such as hardware environmental monitoring and platform event traps are a direct result of the internal presence of service processors in the server.
From the foregoing it should be appreciated that service processors can significantly improve the management of servers by reducing the Mean-Time-To-Resolve an outage. In a world where the availability demands of the IT Network are gradually rising each year, the need to diminish the impact of outages is becoming more and more important. And while the costs of servers may be dropping slightly each year, the cost of data center management has a tendency to rise.